Reversible rotary compressor for refrigerators

ABSTRACT

A reversible rotary compressor for use in refrigerators, in which a suction mechanism and a discharge mechanism are provided in a rotary member which is rotated in the same direction by a rotor of the compressor in frictional engagement therewith, and sucking and discharging operations of said mechanisms are automatically switched by changing the direction of rotation of said rotor; and which, therefore, is completely free of back flow of gas, is operable with minimum power consumption, has a constant compressing ability in both the counterclockwise rotation and the clockwise rotation of the rotor, has a minimum number of suction ports and hence a minimum top clearance volume, and is high in compressing efficiency. By employing the compressor in heat pump-type air conditionars, there can be obtained such an advantage that the operation of the air conditioner can be switched from cooling operation to heating operation or vice versa, only by changing the direction of rotation of the compressor rotor without using a directional control valve in a refrigerant circuit, which has been indispensable heretofore.

United States Sawai et al.

73 atent 1 1 1541 REVERSIBLE ROTARY COMPRESSOR FOR REFRIGERATORS [75]Inventors: Satoshi Sawai, Kawachinagano; Jusaburo Maekawa,Tondabayashi', Yoshimi Tanaka, Sakai, all of Japan [73] Assignee: DaikinKogyo Co., Ltd., Osaka,

Japan [22] Filed: Dec. 29, 1970 [21] Appl. No.: 102,383

[30] Foreign Application Priority Data Dec. 30, l969 Japan ..44/293 2[52] US. Cl. ..4l8/159, l37/625.21, l37/625.46 [51] Int. Cl ..F0lc21/12, F04c 15/02, F040 29/08 [58] Field of Search 18/159, 160, 239,270; 417/326, 410, 902; 137/625.21, 625.46; 62/84, 470

[56] References Cited UNITED STATES PATENTS l,492,5l2 4/1924 Drinkwater.....62/324 861,626 7 1907 Young 418 159 2,243,466 5 1941 Kucher.....417 410 2,575,524 11 1951 Mitchell... 418 159 1,850,567 3/1932 Roessler418/159 2,343,514 3 1944 McCormack.... .....62 178 2,844,945 7 1958Muffly ..62/278 3,5 l4,225 5/1970 Monden et al. ..4l7/4l0 PrimaryExaminerCarlton R. Croyle Assistant ExaminerJohn J. VrablikAttorneyCushman, Darby & Cushman [57] ABSTRACT A reversible rotarycompressor for use in refrigerators, in which a suction mechanism and adischarge mechanism are provided in a rotary member which is rotated inthe same direction by a rotor of the compressor in frictional engagementtherewith, and sucking and discharging operations of said mechanisms areautomatically switched by changing the direction of rotation of saidrotor; and which, therefore, is completely free of back flow of gas, isoperable with minimum power consumption, has a ,constant compressingability in both the counterclockwise rotation and the clockwise rotationof the rotor, has a minimum number of suction ports and hence a minimumtop clearance volume, and is high in compressing efficiency. Byemploying the compressor in heat pump-type air conditionars, there canbe obtained such an advantage that the operation of the air conditionercan be switched from cooling operation to heating operation or viceversa, only by changing the direction of rotation of the compressorrotor without using a directional control valve in a refrigerantcircuit, which has been indispensable heretofore.

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SHEET 7 BF 7 PRIOR ART I l a Kg -Q INVENTORS j BY W W t3" w W WATTORNEYS REVERSIBLE ROTARY COMPRESSOR FOR REFRIGERATORS This inventionrelates to a reversible rotary compressor adapted for use inrefrigerators, particularly in heat pump-type air conditioners, withwhich the operation of the cooling and heating apparatus canautomatically be switched from cooling operation to heating operation orvice versa, without using a directional control valve which has beenindispensable for conventional heat pump-type air conditioners forchanging the direction of flow of a refrigerant passing througharefrigerant circuit, by reason of the fact that the compressor used inthe conventional apparatus is rotated in one direction only.

The most important problem encountered in reversing the rotatingdirection of the rotor in a compressor is that the positions of thesuction mechanism and the discharge mechanism must alternately bechanged to left or right with respect to the pressure transition point,and this problem has not been solved as yet. it is for this reason thata reversible rotary com pressor has not been in use. The reversiblerotary compressor of the present invention has been achieved by making aspecial device such that 'the suction mechanism and discharge mechanismcan automatically be switched. Conventional compressors forrefrigerators for example, are classified into a reciprocating type anda rotary type. The reciprocating type compressor had the disadvantagethat the flowing direction of a refrigerant cannot be reversed, whilethe rotary type compressor had the disadvantage that, since a suctionport only is provided on the suction side and a discharge port only isprovided on the discharge side with respect to the pressure transitionpoint, the sucking and discharging directions are inevitably fixed andthe practical use of the compressor as a reversible compressor isimpossible.

However, the following type of reversible rotary compressor has beenproposed: Namely, as shown in FIGS. 14 to 16 (wherein partscorresponding to those of the compressor according to the presentinvention are indicated by the same reference numerals), a pair ofsuction ports 29, 29' and a pair of discharge ports 6, 6 are providedthrough the wall ofa cylinder 3 on both sides of a pressure transitionpoint 5 in a compression chamber 4, and a gas passage tube 24 or 18 iscommunicated with a chamber 17 or 17' formed exterior of the compressionchamber 4, so as to provide for reversible operation of the compressor.With such a construction, however, where the compression ratio of gasishigh as incase of a refrigeration cycle, the gas discharged from adischarge valve is so high in pressure that, when the high pressure gasis discharged from the compression chamber 4, for example, through thedischarge port 6, a suction valve 40 is held in a closed position underthe pressure of the gas, but in a suction stroke the suction valve 40 isopened by the force of the pressure gas in the chamber 17, as both thesuction valve 40 and' the discharge valve 7 are in the same chamber 17,and a considerable amount of gas flows back into the compression chamberto be re-compressed therein. Therefore, the gas compressing efficiencyof the compressor becomes inevitably low. Furthermore, in the compressorof the type described above the suction port 6 or 6 generally extendsinto the compression chamber 4 of the cylinder and is large in diameter,so that the top clearance volume is large and the degree of re-expansionof the high pressure gas remaining in such port is also high, making thepractical use of the compressor impossible.

In the present invention a device is made so as to prevent the suctiongas and discharge gas from being mixed only on one side of a pressuretransition point, even when a suction mechanism and a dischargemechanism are provided on both sides of the pressure transition point asin the prior art compressor described above. Namely, according to theinvention a required number of suction openings and discharge openingsare formed in a rotary member which is rotatable through a predeterminedlimited angle along with a rotor, and when gas is sucked into the leftside and discharged from the right side of the pressure transition pointfor example, the discharge opening only of the suction and dischargeopenings on the right side of the rotary member is communicated with agas passage channel and a gas inlet channel is closed by the wall ofsaid rotary member upon rotation of the rotor in a counterclockwisedirection, whereby the back flow of gas as encountered in the prior artcompressor is completely prevented, while upon rotation of the rotor ina clockwise direction, the rotary member is also rotated through thepredetermined angle and the left side discharge opening and the rightside suction opening only are respectively communicated with the gaspassage channels, whereby therelative position of the suction mechanismand the discharge mechanism is switched.

An object of the present invention is to provide a reversible rotarycompressor for use in refrigerators which is so designed that therelative position of a suction mechanism and a discharge mechanism isswitched automatically by the rotation of a rotary member which isrotated in the same direction as a rotor in frictional engagementtherewith when said rotor is reversibly rotated in a counterclockwise orclockwise direction; and which, therefore, is completely free of backflow of compressed gas, is operable with minimum power consumption andhas a constant compressing ability in both the counterclockwise rotationand the clockwise rotation of the compressor.

Another object of the invention is to provide a reversible rotarycompressor of the character described above, wherein said rotary memberis provided with only one suction opening to constitute the suctionmechanism, so as to eliminate excess suction openings on the highpressure side and thereby to minimize the top clearance and enhance thecompressing efficiency.

Still another object of the invention is to provide a reversible rotarycompressor of the character described above, wherein the position ofsaid rotary member to switch the relative position of the suctionmechanism and the discharge mechanism upon completion of its rotationthrough a predetermined angle in frictional engagement with said rotoris set by the abutting engagement of a stopper pin, provided on acylinder or a rear head, with one end of an arcuate groove formed in theouter peripheral edge of said rotary member.

Still another object of the invention is to provide a reversible rotarycompressor of the character described above, wherein a chamber having asilencing effect is provided between said discharge mechanism and a gaspassage tube through which compressed gas in the compression chamber isled to an external refrigeration circuit, whereby the noise of thecompressor can be silenced without providing a separate silencerexternally of the compressor.

A further object of the invention is to provide a reversible rotarycompressor of the character described above, which when employed in aheat pump-type air conditioners, enables the operation of said apparatusto vbe switched from cooling operation to heating operation or viceversa by only changing 'the rotating direction of the compressor,without using a directional control valve in the refrigerant circuit,and further enable the heating rate to be accelerated in the heatingoperation of the apparatus by producing a low pressure dome in a housingof said apparatus and therebyminimizing the refrigerant gas dissolved inlubricating oil by evaporation and enabling the entire heat ofcompression to be utilized by a heat exchanger.

An additional object of the invention is to provide a reversible rotarycompressor of the character described above, wherein the refrigerant gasis caused to flow adjacent radial blades of the rotor during its passagefrom the compression chamber to the external gas passage tube, wherebythe separation of the lubricating oil and the refrigerant gas ispromoted.

FIG. 1 is a cross-sectional side view, taken on the line I,I of FIG. 2,of an embodimentofthe reversible rotary compressor for refrigeratorsaccording to the present invention, which comprises a disc-shaped ro vtary member;

FIG. 2 is a transverse cross-sectional view of the compressor rotatingin a counterclockwise direction, taken on the line II-II of FIG. 1; and

FIG. 3 is a fragmentary transverse cross-sectional view .of thecompressor rotating a clockwise direction, similarly taken on the II-IIof FIG. 1;

FIG. 4 is a cross-sectional side view, taken on the line of IVIV of FIG.5, of another embodiment of the invention, which is a modification ofthe embodiment shown in FIGS. 1 to 3';

FIG. 5 is a transverse cross-sectional view of the compressor of FIG. 4rotating in a counterclockwise direction, taken on the line VV of FIG.4; and

FIG. 6 is a fragmentary transverse cross-sectional view of thecompressor of FIG. 4 rotating in a clockwise direction, similarly takenon the line VV of FIG. '4;

FIG. 7 is a cross-sectional side view, taken on the line .VIIVII of FIG.8, of still another embodiment of the invention, which comprises aring-shaped rotary member;

FIG. 8 is a transverse cross-sectional view of the compressor of FIG. 7taken on the line VIII-VIII of FIG. 7;

FIG. 9 is a side view of the cylinder looking in the i direction of thearrows IXIX of FIG. 8;

FIG. 10 is a developed side view of the ring-shaped rotary member;

FIG. 11 is a transverse cross-sectional view, taken on the line ofVIII-VIII of FIG. 7, of still another embodiment of the invention whichis a modification of the embodiment shown in FIGS. 7 to 10;

FIG. 12 is a side view of the cylinder looking in the direction of thearrows XII-XII of FIG. 11;

FIG. 13 is a developed side view of the rotary member used in theembodiment of FIG. 11;

- FIG. 14 is a plan view, partially broken away, of a conventionalrotary compressor; and

shown an embodiment of the compressor according to' the presentinvention in which a rotary guide plate having one suction openingformed therein is interposed as a rotary member between a rotor and achamber so as to. be driven by the friction with the rotating rotor. Thesuction opening may be shifted to the left or right by the rotation ofthe rotary guide plate. As shown in FIG. 1, an electric motor and acompressing mechanism are air-tightly accommodated in a housing 19 ofthe compressor. Namely, the compressor is a so-called sealed compressor.The electric motor is composed of a stator and a rotor 22, while thecompressing mechanism is composed of a front head 1 supporting thestator 25; a

rear head 14 disposed below said front head, and a.

cylinder 3, a rotor 2' and a disc-shaped rotary guide plate 10 which areinterposed between said front head 1 and said rear head 14. A rotorshaft 2 is provided coaxially with the front head 1 and extended intothe rotor 22 of the electric motor. The rotor 2' integral with the rotorshaft 2 is eccentrically mounted in a compression chamber 4 defined bythe cylinder 3. The rotor 2' is in contact with the wall of thecompression chamber 4 at a pressure transition point 5, dividing saidcompression chamber 4 into a low pressure side and a high pressure side.The cylinder 3 is provided with discharge ports 6, 6' each on eachside'of the pressure transition point 5, and at the outer ends of saiddischarge ports 6, 6 are respectively provided with discharge valves 7,7' to prevent back flow of discharge gas and valve guards 27, 27' tolimit the openings of said discharge valves 7, 7 These two dischargeports, discharge valves and valve guards constitute a dischargemechanism. A side cover 9 is secured to the cylinder 3 by means of bolts32 and the space defined by said side cover 9 and the cylinder 3 isdivided into two chambers 17,17 by a partition wall 8'integral with saidside cover 9. The discharge ports 6, 6' are communicated with thechambers 17, 17' through the discharge valves 7, 7 respectively.

Reference numeral 10 designates a rotary member which constitutes asuction mechanism which is the essential portion of the presentinvention. The rotary member. 10 consists of a disc-shaped rotaryguideplate rotatably loosely mounted in the cylinder 3 and having onesuction opening 11 axially bored therethrough. The rotary guide plate 10is in plane contact with the lower surface of the rotor 2', so as to berotated in the same direction by the friction with the side surface ofthe rotor 2 and the side surfaces of blades 28. An arrangement is madesuch that the rotary guide plate is rotatably only through apredetermined angle so that the suction opening 11 may be shifted to theleft or right of the pressure transition .point 5 and positioned on thelow pressure side of the compression chamber 4 when the rotor 2' rotatesin a counterclockwise direction as indicated by the solid line arrow orin a clockwise direction as indicated by the dotted line ar-' row.Namely, in the embodiment of FIGS. 1 to 3 the rotary guide plate isformed in the peripheral edge thereof with an arcuate groove 13'extending over the circumferential length corresponding to the aforesaidpredetermined angle, while the cylinder 3 is provided with a fixedstopper pin 13 which is received in said arcuate groove 13 of the rotaryguide plate 10, and the rotary guide plate 10 is positioned with thesuction opening 11 located on the low pressure side of the compressionchamber 4, by the abutting engagement of the stopper pin 13 with eitherend of the arcuate groove 13. Modifications and changes are of coursepossible to the details of such arrangement.

Namely, the stopper pin 13 may be provided on the rear head 14 disposedbelow the cylinder 3, as shown in the embodiment of FIGS. 4 to 6. Inthis case, the rotor 2' is mounted interior of the cylinder 3 and thearcuate groove 13 of the rotary guide plate 10 is provided at a portionadjacent the outer periphery of the rotor 2.

As stated, in the embodiment of FIGS. 1 to 3 the sliding blades 28 areprovided on the rotor 2' and the totary guide plate 10 is rotated by thefriction with said rotor 2' and sliding blades 28. However, such slidingblades 28 are not essential and retractable partition blades (blades ofthe type indicated at 5 in FIGS. 15 and 16) may be provided instead ofthe sliding blades 28. In this case, the rotary guide plate 10 isrotated only by the friction with the rotor 2.

The rear head 14 which is disposed below the cylinder 3 and axiallysupports the rotary guide plate 10, has a rib 15 by which the interiorof the rear head 14 is divided at substantially the center thereof intotwo chambers 16, 16 which serve as silencer. The rib 15 is in sealingcontact with the partition wall 8 of the side cover 9 which is securedto the cylinder 3, and the chambers 16, 16' inthe rear head 14 arecommunicated with the chambers 17, 17' in the side cover 9 respectively.Thus, when the rotor 2' rotates, the suction opening 11 bored axiallythrough the rotary guide plate 10 is rotated in the same direction andbrought into communication with the chamber 16 or 16 in the rear head14. Reference numeral 31 designates bolts by which the cylinder 3 andthe rear head 14 are secured to the front head 1, and 34 designatesamember by which the electric motor and the compressing mechanism aresecurely mounted in the housing 19.

The member 34 is formed with an oil passage hole 35 at the centerthereof, through which lubricating oil 33 stored in the lower portion ofthe cavity in the housing 19 is sucked upwardly, and also provided witha suitable number of refrigerant gas releasing holes 36 at a shoulderthereof. The lubricating oil 33 sucked up through the oil passage hole35 is supplied to the front head 1 and other portions to be lubricated,through oil passage holes formed in the center of the rear head 14, therotary guide plate 10 and the rotor 2' respectively and thence throughoil passage channels formed in the outer peripheral surface of the shaftof the rotor 2.

Reference numeral 18 designates a gas passage tube whichextendsair-tightly into the housing 19 and communicates with the chamber16' in the rear head 14 but does not communicate with the cavity 20in'the housing 19. Another gas passage tube 24 extends airtightly intothe housing 19 and communicates with the cavity 20 in the housing 19. Agas passage tube 21 disposed interior of the housing 19 has its lowerend communicated with the chamber 16 and its open upper end locatedadjacent lower radial blades 23 fixed to the rotor 22 of the electricmotor. Reference numeral 23' designates upper radial blades fixed to therotor 22. The stator 25 of the electric motor is secured to the fronthead 1 by bolts 30 and supplied with a power from an external powersource through a terminal 26 which is air-tightly fitted in the housing19.

When the rotor shaft 2 is driven. in the direction of the solid linearrow (FIG. 2), the rotary guide plate 10 is rotated in the samedirection by the friction with the side surface of the rotor 2' and theside surfaces of the sliding blades 28, and is brought into a positionas determined by one end of the arcuate groove 13' of said rotary guideplate 10 and the stopper pin 13 provided on the rear head 14, in whichthe suction opening 11 is located on the low pressure'side of thecompression chamber 4 (on the left side of the pressure transition point'5 as viewed in FIG. 2). Under such condition, the gas sucked into thecompressor through the gas passage tube 18 flows into the low pressureside of the compression chamber 4 of the cylinder 3 through the rearhead chamber 16' and the suction opening 11. The gas compressed in thecompression chamber 4 by the ordinary means is led into the rear headchamber 16 through the discharge port 6 on the high pressure side andthe chamber 17, wherein it is expanded and silenced, and then introducedinto the internal gas passage tube 21. Then, the gaseous refrigerant isseparated from the lubricating oil by the radial blades 23 of the rotor22, and discharged through the other gas passage tube 24 after passingthrough the cavity 20 in the housing 19.

On the other hand, when the rotor shaft 2 rotates reversely in thedirection of the dotted line arrow (FIG. 3), the rotary guide plate 10is rotated in the reverse direction and positioned on the opposite sideto the preceding case with respect to the pressure transition point 5(on the right side as viewed in FIG. 3), by the abutting engagementbetween the other end of the arcuate groove 13' and the stopper pin 13.In this case, the gas is sucked into the cavity 20 of the housing 19through the other gas passage tube 24 and after being separated from thelubricating oil by the radial blades 23 of the rotor, introduced intothe rear head chamber 16 through the internal gas passage tube 21 andthence into the low pressure side of the compression chamber 4 throughthe suction opening 11 in the rotary guide plate 10. The gas compressedin the compression chamber 4 by the ordinary means flows from the highpressure side of said compression chamber 4 into the rear head chamber16' through the discharge port 6' and the chamber 17' and is dischargedthrough the gas passage tube 18. In the cavity 20 of the housing 19, ahigh pressure appears when the compressor is driven in the direction ofthe solid line arrow, and a low pressure appears when the same is drivenreversely in the direction of the dotted line arrow.

In the above-described operation, since the only one suction opening 11formed in the rotary guide plate 10 is located on the low pressure sideand not on the high pressure side of the compression chamber 4, nocompressed gas is allowed to flow backward from the com-.

mechanism. In this embodiment of the compressor, a

ring-shaped rotary guide plate coaxially loosely mounted in the cylinderand a rotor is eccentrically disposed within said rotary guide plate 10,said rotary guide plate 10 being rotated by the friction with said ro- 1tor, whereby the suction and discharge operations are accomplished. Theother portions of the construction are the same as in the embodimentshown in FIGS. 1 to 6, and the corresponding parts are designated by thesame reference numerals.

Namely, FIGS. 7 to 10 shows another embodiment of the invention in whichthe rotary guide plate 10 is formed therein with one suction opening andtwo discharge openings. As shown, the cylinder 3 is provided withasuction port 29 and a discharge port 6 which are open into the chamber17 on one side of the partition wall 8 of the side cover 9, a dischargevalve 7 and avalve guard 17 to limit the degree of opening of saiddischarge valve 7', and also with a suction port 29' I and a dischargeport 6 which are open into the chamber 17' on the other side of thepartition wall 8, a discharge valve 7' and a valve guard 27' to limitthe degree of opening of said discharge valve 7'. As shown in FIG. 9,the suction ports 29, 29 and the discharge ports 6, 6 are respectivelyprovided in the same horizontal planes perpendicular to the axis ofrotation, i.e. the discharge ports 6, 6 are provided in one horizontalplane and the suction ports 29, 29 are provided in another horizontalplane; and the suction port 29 and the discharge port 6, and the suctionport 29" i and the discharge port 6' are respectively provided in thesame vertical planes parallel to the axis of rotation. On the otherhand, the rotary guide plate 10 rotatably loosely mounted in thecylinder 3 is provided therethrough with one suction opening 11 and twodischarge, openings 12, 12' on both sides of said suction opening 11 inthe manner shown in FIG. 10, i.e. the discharge openings 12, 12' arelocated in two different vertical planes parallel to the axis ofrotation respectively but on the same horizontal plane perpendicular tothe axis of rotation. The circumferential distance a between the suctionopening 11 and the discharge opening 12 and between the suction opening11 and. the discharge opening 12' is equal to the circum- (FIGS. 9 and10). The two suction ports 29, 29' in the cylinder 3 and the suctionopening 1] in the rotary guide plate 10 constitute a suction mechanism,while the two discharge ports 6, 6 in the cylinder 3 and the twodischarge openings 12, 12' in the rotary guide plate 10 constitute adischarge mechanism. The other arrangement is identical with thepreceding embodiment.

With the construction described above, when the rotor shaft 2 rotates inthe direction of the solid line arrow in FIG. 8, the rotary guide platel0'is rotated in the same direction by the friction with the outerperipheral surface of the rotor 2' and the outer edge surfaces of thesliding blades 28, and is set in a position as determined by the stopperpin 13 provided on the rear head 14 and abutting against one end of thearcuate groove 13 formed in the peripheral edge of said rotary guideplate 10 over a circumferential length corresponding to a predeterminedangle of rotation of said rotary guide plate 10.- In this position ofthe rotary guide plate 10, the discharge port 6' on the low pressureside and the suction port 29 on the high pressure side of the cylinder 3are closed by the wall of said rotary guide plate 10, and the suctionopening 11 and the discharge opening 12 of said rotary guide plate 10are communicated with the suction port 29' and the discharge port 6 ofthe cylinder 3 respectively. On the other hand, when the rotor shaft 2rotates in a reverse direction indicated by the dotted line arrow inFIG. 8,

the rotary guide plate 10 is set in a position by the stopper pin 13abutting against the other end of the arcuate groove-13, and in thisposition the discharge port 6 on the low pressure side and the suctionport 29' on the high pressure side of the cylinder 3 are closed by thewall of. said rotary guide plate 10, and the suction opening 11 and thedischarge opening 12' of said rotary guide plate are communicated withthe suction port 29 and the discharge port 6' of the cylinder 3respectively. The other function of the compressor is identical with thecase of the preceding embodiment.

In the above-described operation, since the suction port 29 or 29' onthe high pressure side of the cylinder 3 is closed by the wall of therotary guide plate 10 as stated above, the back flow of the-compressedgas is completely prevented. A still another embodiment of theinvention, which is similar'to the embodiment of FIGS. 7 to 10, is shownin FIGS. 11 to 13, in which the rotary guide plate 10 is provided withone discharge opening and two suction openings. on both sides of saiddischarge opening. In this embodiment, the two discharge ports 6, 6' andtwo suction ports 29, 29-provided in and the two discharge valves 7, 7providedon the cylinder 3 are the same as those in the embodiment ofFIGS. 8 to 10 and, therefore, the description thereof will beomittedrThe rotary guide plate 10 is provided with one discharge opening12 and two suction openings 11, 11 on both sides of said dischargeopening 12, all of said ports extending perpendicularly of the axis ofrotation. The circumferential distance a between the discharge opening12and the suction openings ll, 11 is equal to the. circumferentialdistance a between the discharge ports 6, 6' and between the suctionports 29, 29" of the cylinder 3, and

the axial distance b between the discharge opening 12 and the suctionopenings 11,11 of the rotary guide plate 10 is equal to the axialdistance b between the discharge ports 6, 6' and the suction. ports 29,29 of the cylinder 3. The two suction ports 29, 29' of'the cylinder 3and the suction openings 11, 11 of the rotary guide plate constitute asuction mechanism, and the two discharge ports 6, 6' of the cylinder 3and the one discharge opening 12 of the rotary guide plate 10 constitutea discharge mechanism. The other arrangement is identical with theembodiment of FIGS. 7 to 10 and the embodiment of FIGS. 1 to 3.

With such construction, when the rotor shaft 2 rotates in the directionindicated by the solid line arrow in FIG. 11, the rotary guide plate 10is rotated in the same direction by the frinction with the rotor 2' andthe sliding blades 28 and set in a position determined by the stopperpin 13 provided on the rear head 14 and abutting against one end of thearcuate groove 13 formed in the outer peripheral edge of said rotaryguide plate 10 over a circumferential length corresponding to apredetermined angle of rotation of said rotary guide plate. In thisposition of the rotary guide plate 10, the discharge opening 12 and thesuction opening 11' of said rotary guide plate are communicated with thedischarge port 6 and the suction port 29 of the cylinder 3 respectively,and the suction port 29 on the high pressure side and the discharge port6' on the low pressure side of the cylinder 3 are closed by the wall ofsaid rotary guide plate 10.

On the other hand, when the rotor shaft 2'rotates in an oppositedirection indicated by the dotted line arrow in FIG. 11, the rotaryguide plate 10 is set in such a position, by the abutting engagementbetween the stopper pin 13 and the other end of the arcuate groove 13',that the suction opening 11 and the discharge opening 12 of said rotaryguide plate are communicated with the suction port 29 and the dischargeport 6' of the'cylinder 3 respectively, and suction port 29' on the highpressure side and the discharge port 6 on the low pressure side of thecylinder 3 are closed by the wall of the ring-shaped rotary guide plate10. The other function of the compressor is identical with the cases ofthe preceding embodiments.

According to the embodiment of the invention described and illustratedherein, it is possible to automatically control the direction of suctionor discharge by the friction between rotor and rotary member, only bychanging the rotating direction of the rotor of the compressor withoutthe necessity of providing special parts. However, it should beunderstood that the present invention is not restricted only to theembodiments shown but many modification and changes are of coursepossible to the details of the construction without deviating from thespirit of the invention, for

instance, by inverting the relative position between the rotor, and therotary guide plate and the rear head in the embodiment of FIGS. 1 to 3.

According to the present invention, as described hereinabove, a suctionmechanism and a discharge mechanism are provided in the rotary memberand the cylinder, which rotary member is mounted in cylinder and rotatedby the friction with the rotor, and after rotation of the rotary member,the discharge mechanism and suction mechanism which were in use beforethe rotation are completely closed to the state wherein no suction portis present on the high pressure side or a suction port on the highpressure side is closed. Therefore, no compressed'gas is ever allowed toflow backward from the high pressure side chamber into the compressionchamber. Thus, a highly efficient compressing effect can be obtainedwith a minimum power consumption and constant compressing efficiency.

Further, the type of compressor shown in FIGS. 1 to 6 or FIGS. 7 to 10which is provided with only one suction port or suction opening, enablesan extremely high compressing efficiency to be obtained as no surplussuction ports are present on the high pressure side and the so-calledtop clearance volume, i.e., the phenomenone in which the high pressurecompressed gas remaining in the suction port which is previously on thedischarge side, re-expands in the suction stroke, can becompletelyeliminated.

The compressor according to the present invention is highly suitable foruse in heat pump-type air conditioners. The air conditionersincorporating the compressor of this invention have such an advantagethat the operation of the air conditioner can be switched from coolingoperation to heating operation or vice verse by only changing therotating direction of the compressor, without using a refrigerantcircuit changeover valve which has been indispensable for theconventional air conditioners.

According to the present invention, since the compressed gas is expandedand silenced in the interior of the rear head before it is dischargedfrom the compression chamber to the outside through the discharge port,there is no necessity for providing a separate silencer, and further,since the interior gas passage tube for communicating the cavity in thehousing with the compression chamber therethrough is disposed adjacentthe radial blades fixed to the rotor of the electric motor, theseparation of the lubricating oil and the refrigerant gas is promoted.

In conventional high pressure dome-type air conditioners a largequantity of heat is radiated from the housing during heating operation.Moreover, a refrigerant contained in lubricating oil in a high pressurecircuit is not evaporated until after the housing is sufficientlyheated, so that a considerably long time is required before hot airheated to a predetermined temperature is obtained in the initial stageof the heating operation, due to a shortage in quantity of thecirculating refrigerant. However, by employing the compressor of theinvention as a heat pump, a low pressure dome is produced within thehousing and the quantity of the refrigerant circulating in the initialstage of the heating operation can be increased, so that the effectiveuse of the heat of condensation becomes possible and the time requiredbefore the hot air is obtained can be shortened. It is also to be notedthat the compressor of the present invention can be easily produced onlyby slightly modifying the conventional ones and, therefore, is low incost. Thus, the present invention is of great practical value.

What is claimed is:

l. A reversible rotary compressor, for use in refrigerators, of the typewhich has a compressing mechanism, including:

a front head;

a rear head;

a cylinder disposed between the front and rear heads;

a rotor disposed eccentrically in said cylinder to define a compressionchamber between the rotor and the cylinder longitudinally divided byadjacency of the cylinder and rotor, at a pressure transition point,into a low pressure side and a high pressure side;

a motor driving the rotor for sucking refrigerant gas into anddischarging refrigerant gas from the compression chamber;

said compressor comprising:

a rotary member in frictional engagement with the rotor for rotationthrough a predetermined limited angle with the rotor, irrespective ofthe angular sense of rotation of the rotor;

a first suction conduit mechanism communicated with the compressionchamber angularly to one side of the pressure transition point;

a first discharge conduit mechanism communicated with the compressionchamber angularly to the opposite side of the pressure transition point;

a second suction conduit mechanism communicated with the compressionchamber angularly to said opposite side of the pressure transitionpoint;

a second discharge conduit mechanism communicated with the compressionchamber angularly to said one side of the pressure transition point; and

means responsive to the direction of rotation of said rotary member forclosing both first conduit mechanisms and opening both said secondconduit mechanisms, alternately, to respectively provide for normal andreverse rotation operation of the compressor. 2. The reversible rotarycompressor of claim 1 further comprising:

a first gas passage tube;

a second gas passage tube;

means alternately communicating the first discharge and second suctionconduit mechanisms with the I first gas passage tube; and

means alternately communicating the second suction and first dischargeconduit mechanisms with the second gas passage tube.

3. The reversible rotary compressor of claim 2 wherein the dischargeconduit mechanisms include:

a first discharge port provided through the cylinder angularly to oneside of the pressure transition point; and a first discharge valve foropening and closing the first discharge port;

a second discharge port provided through the cylinder angularly to theopposite side of the pressure transition point; and a second dischargevalve for opening and closing the second discharge port;

said rotary member being constituted by a discshaped rotary guide platedisposed in said cylinder and having means defining an opening axiallytherethrough for alternately forming a part of both of said suctionconduit mechanisms, so that as said rotary guide plate is angularlyshifted between the extremes of said predetermined limited angle, theaxial opening is alternately communicated with the first compressionchamber angularly clockwise from the pressure transition point andangularly counterclockwise from the pressure transition point, in bothinstances on the low pressure side of the pressure transition point.

4. The reversible rotary compressor of claim 3.

wherein said rotary guide plate has means defining an arcuate grooveformed in the outer periphery thereof and extending arcuately an amountcorresponding to said predetermined limited angle, one of said cylinderand said rear head having pin means mounted thereon and received in saidgroove for limiting angular movement of said rotary guide plate to saidpredetermined,

limited angle.

5. The reversible rotary compressor of claim 2, wherein the dischargeconduit mechanisms include:

a first discharge port provided through the cylinder angularly to oneside of the pressure transition point; and a first discharge valve foropening and closing the first discharge port;

a second discharge port provided through the cylinder angularly to theopposite side of the pressure transition point; and a second dischargevalve for opening and closing the second discharge port;

a second suction port provided radially through the cylinder on the sameside of the pressure transition point as the first discharge port;

a first suction port provided radially through the cylinder on the sameside of the pressure transition point as the second discharge port;

the two discharge portsopening radially outwardly at a plane axiallyspaced from that of the two suction ports; i

the first suction port and the second discharge port opening in acommon'plane parallel to the axis of rotation of the rotary member; 7

thelsecond suction port and the first discharge port opening in anothercommon plane parallel to the axis of rotation of the rotary member;

the rotary member being constituted by a ringshaped rotary guide platejournalled in the cylinder for rotation around the rotor;

said guide plate having means defining:

one suction opening radially therethrough and two discharge openingsradially therethrough, o'ne disposed angularly to each side of the onesuction opening; the relative spacing, angularly of said. axis ofrotation, of said one suction opening and each of said two dischargeopenings, being equal to that of said first and second suction ports andto that of said first and second discharge ports; the relative spacing,axially of said axis of rotation, of said one suction opening and saidtwo discharge openings being equal to that of said the two dischargeports and the two suction ports, the rotary guide plate being rotatedbetween the extremes thereof in dependence uponthe direction of rotationof the rotor to align the respective ports and openings.

6. The reversible rotary compressor of claim 5 wherein said rotary guideplate has means defining an arcuate groove formed in the outer peripherythereof and extending arcuately an amount corresponding to saidpredetermined limited angle, one of said cylinder and'said rear headhaving pin means mounted thereon and received in said groove forlimiting angular movement of said rotary guide plate to saidpredetermined, limited angle. I

7. The reversible rotary compressor of claim 2, wherein the dischargeconduit mechanisms include;

a first discharge port providedthrough the cylinder angularly toone sideof the pressure transition point; and a first discharge valve foropening and 2 closing the first discharge port;

a second discharge port provided through the cylinder angularly to theopposite side of the pressure transition point; and a second dischargevalve for opening and closing the second discharge port;

a second suction port provided radially through the cylinder on the sameside of the pressure transition point as the first discharge port;

a first suction port provided radially through the cylinder on the sameside of the pressure transition point asthe second discharge port;

the two discharge ports opening radially outwardly at a plane axiallyspaced from that of the two suction ports;

the first suction port and the second discharge port opening in a commonplane parallel to the axis of rotation of the rotary member;

the second suction port and the first discharge port opening in anothercommon plane parallel to the axis of rotation of the rotary member;

the rotary member being constituted by a ringshaped rotary guide platejournalled in the cylinder for rotation around the rotor;

said guide plate having means defining:

one discharge opening radially'therethrough and two suction openingsradially therethrough, one disposed angularly to each side of the onedischarge opening; the relative spacing, angularly of said axis ofrotation, of said one discharge opening and each of said two suctionopenings, being equal to that of said first and second discharge portsand to that of said first and second suction ports; the relativespacing, axially of said axis of rotation, of said one discharge openingand said two suction openings being equal to that of said thetwodischarge ports and the two suction ports, the rotary guide platebeing rotated between the extremes thereof in dependence upon thedirection of rotation of the rotor to align the respective ports andopenings.

8. The reversible rotary compressor of claim 7 wherein said rotary guideplate has means defining an arcuate groove formed in the outer peripherythereof and extending arcuately an amount corresponding to saidpredetermined limited angle, one of said cylinder and said rear headhaving pin means mounted thereon and received in said groove forlimiting angular movement of said rotary guide plate to saidpredetermined,

limited angle.

9. The reversible rotary compressor of claim 2 further including:

means directly connecting said electric motor and said rotor;

a housing;

said electric motor, rotor and directly connecting means being sealedwithin said housing;

the first gas passage to be sealingly communicating alternately with thetwo respective conduit mechanisms via the cavity defined within saidhousing outside said electric motor, rotor and directly connecting meansin dependence upon the direction of rotation of said rotor;

the second gas passage tube directly sealing communicating alternativelywith the other two respective conduit mechanisms in sealed isolationfrom said cavity in dependence upon the direction of rotation of saidrotor; 10. The reversible rotary compressor of claim 9 wherein the twodischarge conduit mechanisms comprise two discharge. ports providedthrough the cylinder on respective sides of the pressure transitionpoint; means sealingly dividing the interior of the rear head into twochambers; one of the chambers and a respective one of said dischargeports being communicated with said first gas passage tube; and the otherof said discharge ports, the other of said chambers, said cavity beingcommunicated with the second gas passage tube, whereby the compressedgas from the high pressure side of the pressure transition line isexpanded and silenced in a respective one of said chambers, depending onthe direction of rotation of the rotor, before being discharged througha respective one of the discharge p'orts through the respective gaspassage tube.

11. The reversible rotary compressor of claim 10, wherein the electricmotor includes a rotor having a plurality of radial blades; an interiorgas passage tube having one end disposed adjacent said blades and theother end in communication with the first-mentioned of said chambers.

1. A reversible rotary compressor, for use in refrigerators, of the typewhich has a compressing mechanism, including: a front head; a rear head;a cylinder disposed between the front and rear heads; a rotor disposedeccentrically in said cylinder to define a compression chamber betweenthe rotor and the cylinder longitudinally divided by adjacency of thecylinder and rotor, at a pressure transition point, into a low pressureside and a high pressure side; a motor driving the rotor for suckingrefrigerant gas into and discharging refrigerant gas from thecompression chamber; said compressor comprising: a rotary member infrictional engagement with the rotor for rotation through apredetermined limited angle with the rotor, irrespective of the angularsense of rotation of the rotor; a first suction conduit mechanismcommunicated with the compression chamber angularly to one side of thepressure transition point; a first discharge conduit mechanismcommunicated with the compression chamber angularly to the opposite sideof the pressure transition point; a second suction conduit mechanismcommunicated with the compression chamber angularly to said oppositeside of the pressure transition point; a second discharge conduitmechanism communicated with the compression chamber angularly to saidone side of the pressure transition point; and means responsive to thedirection of rotation of said rotary member for closing both firstconduit mechanisms and opening both said second conduit mechanisms,alternately, to respectively provide for normal and reverse rotationoperation of the compressor.
 2. The reversible rotary compressor ofclaim 1 further comprising: a first gas passage tube; a second gaspassage tube; means alternately communicating the first discharge andsecond suction conduit mechanisms with the first gas passage tube; andmeans alternately communicating the second suction and first dischargeconduit mechanisms with the second gas passage tube.
 3. The reversiblerotary compressor of claim 2 wherein the discharge conduit mechanismsinclude: a first discharge port provided through the cylinder angularlyto one side of the pressure transition point; and a first dischargevalve for opening and closing the first discharge port; a seconddischarge port provided through the cylinder angularly to the oppositeside of the pressure transition point; and a second discharge valve foropening and closing the second discharge port; said rotary member beingconstituted by a disc-shaped rotary guide plate disposed in saidcylinder and having means defining an opening axially therethrough foralternately forming a part of both of said suction conduit mechanisms,so that as said rotary guide plate is angularly shifted between theextremes of said predetermined limited angle, the axial opening isalternately communicated with the first compression chamber angularlyclockwise from the pressure transition point and angularlycounterclockwise from the pressure transition point, in both instanceson the low pressure side of the pressure transition point.
 4. Thereversible rotary compressor of claim 3 wherein said rotary guide platehas means defining an arcuate groove formed in the outer peripherythereof and extending arcuately an amount corresponding to saidpredetermined limited angle, one of said cylinder and said rear headhaving pin means mounted thereon and received in said groove forlimiting angular movement of said rotary guide plate to saidpredetermined, limited angle.
 5. The reversible rotary compressor ofclaim 2, wherein the discharge conduit mechanisms include: a firstdischarge port provided through the cylinder angularly to one side ofthe pressure transition point; and a first discharge valve for openingand closing the first discharge port; a second discharge port providedthrough the cylinder angularly to the opposite side of the pressuretransition point; and a second discharge valve for opening and closingthe second discharge port; a secOnd suction port provided radiallythrough the cylinder on the same side of the pressure transition pointas the first discharge port; a first suction port provided radiallythrough the cylinder on the same side of the pressure transition pointas the second discharge port; the two discharge ports opening radiallyoutwardly at a plane axially spaced from that of the two suction ports;the first suction port and the second discharge port opening in a commonplane parallel to the axis of rotation of the rotary member; the secondsuction port and the first discharge port opening in another commonplane parallel to the axis of rotation of the rotary member; the rotarymember being constituted by a ring-shaped rotary guide plate journalledin the cylinder for rotation around the rotor; said guide plate havingmeans defining: one suction opening radially therethrough and twodischarge openings radially therethrough, one disposed angularly to eachside of the one suction opening; the relative spacing, angularly of saidaxis of rotation, of said one suction opening and each of said twodischarge openings, being equal to that of said first and second suctionports and to that of said first and second discharge ports; the relativespacing, axially of said axis of rotation, of said one suction openingand said two discharge openings being equal to that of said the twodischarge ports and the two suction ports, the rotary guide plate beingrotated between the extremes thereof in dependence upon the direction ofrotation of the rotor to align the respective ports and openings.
 6. Thereversible rotary compressor of claim 5 wherein said rotary guide platehas means defining an arcuate groove formed in the outer peripherythereof and extending arcuately an amount corresponding to saidpredetermined limited angle, one of said cylinder and said rear headhaving pin means mounted thereon and received in said groove forlimiting angular movement of said rotary guide plate to saidpredetermined, limited angle.
 7. The reversible rotary compressor ofclaim 2, wherein the discharge conduit mechanisms include: a firstdischarge port provided through the cylinder angularly to one side ofthe pressure transition point; and a first discharge valve for openingand closing the first discharge port; a second discharge port providedthrough the cylinder angularly to the opposite side of the pressuretransition point; and a second discharge valve for opening and closingthe second discharge port; a second suction port provided radiallythrough the cylinder on the same side of the pressure transition pointas the first discharge port; a first suction port provided radiallythrough the cylinder on the same side of the pressure transition pointas the second discharge port; the two discharge ports opening radiallyoutwardly at a plane axially spaced from that of the two suction ports;the first suction port and the second discharge port opening in a commonplane parallel to the axis of rotation of the rotary member; the secondsuction port and the first discharge port opening in another commonplane parallel to the axis of rotation of the rotary member; the rotarymember being constituted by a ring-shaped rotary guide plate journalledin the cylinder for rotation around the rotor; said guide plate havingmeans defining: one discharge opening radially therethrough and twosuction openings radially therethrough, one disposed angularly to eachside of the one discharge opening; the relative spacing, angularly ofsaid axis of rotation, of said one discharge opening and each of saidtwo suction openings, being equal to that of said first and seconddischarge ports and to that of said first and second suction ports; therelative spacing, axially of said axis of rotation, of said onedischarge opening and said two suction openings being equal to that ofsaid the two discharge ports and the two suction ports, the rotary guideplate beIng rotated between the extremes thereof in dependence upon thedirection of rotation of the rotor to align the respective ports andopenings.
 8. The reversible rotary compressor of claim 7 wherein saidrotary guide plate has means defining an arcuate groove formed in theouter periphery thereof and extending arcuately an amount correspondingto said predetermined limited angle, one of said cylinder and said rearhead having pin means mounted thereon and received in said groove forlimiting angular movement of said rotary guide plate to saidpredetermined, limited angle.
 9. The reversible rotary compressor ofclaim 2 further including: means directly connecting said electric motorand said rotor; a housing; said electric motor, rotor and directlyconnecting means being sealed within said housing; the first gas passageto be sealingly communicating alternately with the two respectiveconduit mechanisms via the cavity defined within said housing outsidesaid electric motor, rotor and directly connecting means in dependenceupon the direction of rotation of said rotor; the second gas passagetube directly sealing communicating alternatively with the other tworespective conduit mechanisms in sealed isolation from said cavity independence upon the direction of rotation of said rotor;
 10. Thereversible rotary compressor of claim 9 wherein the two dischargeconduit mechanisms comprise two discharge ports provided through thecylinder on respective sides of the pressure transition point; meanssealingly dividing the interior of the rear head into two chambers; oneof the chambers and a respective one of said discharge ports beingcommunicated with said first gas passage tube; and the other of saiddischarge ports, the other of said chambers, said cavity beingcommunicated with the second gas passage tube, whereby the compressedgas from the high pressure side of the pressure transition line isexpanded and silenced in a respective one of said chambers, depending onthe direction of rotation of the rotor, before being discharged througha respective one of the discharge ports through the respective gaspassage tube.
 11. The reversible rotary compressor of claim 10, whereinthe electric motor includes a rotor having a plurality of radial blades;an interior gas passage tube having one end disposed adjacent saidblades and the other end in communication with the first-mentioned ofsaid chambers.